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Μελέτες στις ταχέως εξαπλωνόμενες χρηματοοικονομικές κρίσεις με την χρήση υποδειγμάτων απαριθμητών τιμών και δεδομένων διάρκειαςΣιάκουλης, Βασίλειος 18 June 2014 (has links)
Στην παρούσα διατριβή πραγματοποιούμε εμπειρικές αναλύσεις στο αντικείμενο της Χρηματοοικονομικής Μόλυνσης στον χρηματοπιστωτικό τομέα και στις αγορές μετοχών και ομολόγων, με την χρήση υποδειγμάτων απαραριθμητών δεδομένων και δεδομένων διάρκειας. / In the current thesis we focus on Financial Contagion modeling in the domain of bank failures, stock and bond markets, with the use of Count and Duration data models.
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Three Essays In Applied MicroeconomicsCarrion-Flores, Carmen Eugenia January 2007 (has links)
This dissertation applies economic theories and econometric methods to analyze the interactions between government policies and economic agents in two important and current topics: the protection of the environment and illegal migration.Following the introduction, the second chapter studies the empirical strength of bi-directional linkages between environmental standards and performance, on the one hand, and environmental innovation, on the other. Our empirical results reveal that environmental R&D both spurs the tightening of government environmental standards and is spurred by the anticipation of such tightening, suggesting that U.S. environmental policy (at least in the context of the manufacturing industries that we study) has been responsive to innovation and effective in inducing innovation.The third chapter studies whether a voluntary reduction pollution programs can prompt firms to develop new environmental technologies that yield future emission reduction benefits. Conversely, a VRP may induce a participating firm to divert resources from environmental research to environmental monitoring and compliance activities that yield short-term benefits in reduced emissions. We find evidence that higher rates of program participation are associated with significant reductions in the number of successful environmental patent applications four to six years after the program ended.The fourth chapter examines the migration duration of Mexican immigrants in the U.S. using data from the Mexican Migration Project (MMP). In the past, temporary migrations were frequent, and often the rule rather than the exception in the case of Mexican immigrants. This pattern may be changing due to the tightening of the border between Mexico and the Unites States. Moreover, this paper examines whether migration experience, demographic characteristics, economic conditions or social networks drive the time Mexican immigrants to reside illegally in the United States. The empirical analysis shows that the migration duration increases as the U.S. expected real wage increases. Tighter U.S. migration policies have an ambiguous effect on the migration duration while longer distances decrease the hazard of return to their state of origin.In the final chapter of this dissertation, the general findings are concluded and some future avenues of research are discussed.
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Somatinių ląstelių bendrojo bakterinio užterštumo ir kitų kokybės rodiklių kitimo žaliaviniame piene dinamika vidurio Lietuvos pieno perdirbimo įmonėse / The variation of total bacteria count and other quality parameters in raw milk and the dynamics of central Lithuania's milk recast companiesMockaitis, Jonas 13 April 2005 (has links)
Introduction. Milk is one of the most important economies of the country. In 2002, milk contained 20% of the total value of agricultural economy products, and more than 30% of the total value of export of agricultural economy and alimentary products. Milk is going to stay the underlying branch of agricultural economy in the future.
Today, 95.5 % of all Lithuanian farms have 1-4 cows. These farms contain 74.7% of the total number of cows. This producer group is the biggest and most problematic, because its contribution to production of milk is very important. It is important to emphasize, that pensioners contain 45% of milker holders.
Objective of the study. The aim of this master‘s paper is to analyze the composition of Lithuania‘s recast companies according to the data taken from state lab Pieno Tyrimai of procurement raw milk. This paper will also analyze the dynamic of the most important quality parameters including: domain, season, the number of milk providers and the number of tested milk samples.
Materials ant methods. In this master‘s paper the quality and the consistency of raw milk were analyzed according to parameters set by the state lab „Pieno tyrimai“. The subjects of research were the quality and composition data of 2002-2004 year samples of raw milk. Tendencies of resources of raw milk were analyzed according to the newest statutory requirements in Lithuania and in compliance with the main EU legislation.
Findings. According to the analyses of the... [to full text]
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Karvių melžimo operacijų įtaka somatinių ląstelių skaičiui piene / Effect of milking procedures on milk somatic cell countMartinkus, Nerijus 18 March 2008 (has links)
Modernios pienininkystės fermos sėkmė priklauso nuo to, ar joje gaminamas pienas yra aukštos kokybės. Pagrindiniai veiksniai, turintys įtakos somatinių ląstelių skaičiui piene, yra gera melžimo organizacija, melžimo įrangos taisyklingas veikimas, klinikinių mastitų gydymas antibiotikais ir kt. Mokslininkai įrodė, kad melžti karves kas dvylika valandų yra optimaliausia, kai jos melžiamos du kartus per parą. SLS piene daug priklauso nuo taisyklingos melžimo darbotvarkės, kuri apima skirtingas melžimo operacijas (tešmens ir spenių paruošimas melžimui, spenių dirginimas, pirmųjų pieno čiurkšlių numelžimas, melžiklių užmovimas ant spenių, melžiklių numovimas pamelžus ir efektyvi spenių antiseptika po melžimo) ir nuo šių operacijų trukmės. Teisingai atliekamos melžimo procedūros yra svarbios mastito prevencijai ir užtikrina visišką pieno išmelžimą iš tešmens. Tyrėjai įrodė, kad daugiau kaip 50 % melžimo proceso laiko užtrunka pats melžimas. Dabartiniu metu melžimo operacijos vis labiau mechanizuojamos. Netaisyklingas melžimas gali pailginti pieno atleidimo laiką, didėja rizika susirgti tešmens uždegimais. Pablogėja pieno kokybė, todėl gaunami ekonominiai nuostoliai.
Padidėjęs somatinių ląstelių skaičius piene ¬ svarbus mastito požymis. Perdirbamajai pramonei karvių mastitas buvo ir liks vienu iš svarbiausių trukdžių gaminant aukštos kokybės pieno produktus. Klinikine forma serga 2 – 5 % laktuojančių ir užtrūkintų karvių, o slaptuoju uždegimu – iki 50 % karvių. Viena dažniausiai... [toliau žr. visą tekstą] / Data were collected from two dairy farms. On the farm A cows were milked using full automatised milking equipment „Milkmaster“. On the farm B cows were milked with „Interpuls“ milking equipment. The DeLaval milking system was supplied with automatic cluster remover. On dairy farms A and B cows were milked twice daily. The goal of our studies was to analyse consumption of main milking operations (cow udder preparation before milking, milking and over-milking) and their influence on milk somatic cell count. Were selected 20 cows in each farm. The duration of main milking procedures were recorded. Data on milk, fat and protein yields and somatic cell count were collected.The mean duration of pre-milking udder preparation was 42 s (farm A) and 46,03 s (farm B). Some cows were prepared only for 25,50 Afarm A) s, whereas the udder preparation comprised merely inadequate cleaning of teats. The maximum duration of over-milking was 41,10 (farm B).
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A study of factors relevant for the generation of new technology in OECD countries : A cross-sectional analysis of the relationship between stock of knowledge, research effort, competition and knowledge accumulationHedberg, Elisabeth January 2014 (has links)
This thesis investigates, at the country level, the relationship between innovation output or generation of new technology and input factors such as stock of knowledge, research effort and institutional factors such as competition and intellectual property rights. It is shown that variations in generation of new technology reflect differences in knowledge stock, research effort, product market competition and other institutional factors of OECD countries. The available stock of knowledge and the research effort was shown to have a linear and positive effect on technology generation. It was also shown that the degree of product market competition has a nonlinear effect on technology growth, thereby confirming on a country-level an inverted-U relationship between competition and innovation. Generation of new knowledge was examined using a knowledge production function with annual and accumulated knowledge measured with a patent indicator based on a worldwide count of patent priority filings. A cross-sectional linear regression model was used with secondary data. Independent variables included were the main variables accumulated stock of patent priority filings, the number of FTE researchers in R&D and the Product Market Regulation Index. Institutional bias was accounted for by including the independent variables Index of Patent Rights, administrative patenting fees and a Global Competitiveness Index. The Global Competitiveness index was found to have positive effect on patent productivity and the administrative patenting fees relationship was found to be negative. The results are consistent with theories and empirical findings. The results also highlight the importance of innovation policies that keep costs of patenting low and of adjusting the competition policy of a country to the type of economy in question.
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Bayesian analysis for time series of count data2014 July 1900 (has links)
Time series involving count data are present in a wide variety of applications. In many applications, the observed counts are usually small and dependent. Failure to take these facts into account can lead to misleading inferences and may detect false relationships. To tackle such issues, a Poisson parameter-driven model is assumed for the time series at hand. This model can account for the time dependence between observations through introducing an autoregressive latent process.
In this thesis, we consider Bayesian approaches for estimating the Poisson parameter-driven model. The main challenge is that the likelihood function for the observed counts involves a high dimensional integral after integrating out the latent variables. The main contributions of this thesis are threefold. First, I develop a new single-move (SM) Markov chain Monte Carlo (MCMC) method to sample the latent variables one by one. Second, I adopt the idea of the particle Gibbs sampler (PGS) method \citep{andrieu} into our model setting and compare its performance with the SM method. Third, I consider Bayesian composite likelihood methods and compare three different adjustment methods with the unadjusted method and the SM method. The comparisons provide a practical guide to what method to use.
We conduct simulation studies to compare the latter two methods with the SM method. We conclude that the SM method outperforms the PGS method for small sample size, while they perform almost the same for large sample size. However, the SM method is much faster than the PGS method. The adjusted Bayesian composite methods provide closer results to the SM than the unadjusted one. The PGS and the selected adjustment method from simulation studies are compared with the SM method via a real data example. Similar results are obtained: first, the PGS method provides results very close to those of the SM method. Second, the adjusted composite likelihood methods provide closer results to the SM than the unadjusted one.
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Characterization of heterotrophic plate count (HPC) bacteria from biofilm and bulk water samples from the Potchefstroom drinking water distribution system / by S. WalterWalter, Sunette January 2009 (has links)
The presence of heterotrophic plate count (HPC) bacteria in drinking water distribution systems is usually not considered harmful to the general consumer. However, precautions must be taken regarding the immunocompromised. All water supply authorities in South Africa are lawfully required to provide consumers with high-quality drinking water that complies with South African-and international standards. This study mainly focused on the isolation, identification and characterization of HPC and other bacteria from biofilm-and bulk water samples from two sampling points located within the Potchefstroom drinking water distribution system. Based on five main objectives set out in this study, results indicated that the bulk water at the J.S. van der Merwe building was of ideal quality fit for lifetime consumption. Application of enrichment-and selective media allowed for the isolation of 12 different bacterial morphotypes. These were identified by way of biochemical-and molecular methods as Bacillus cereus, Bacillus subtilis, Brevundimonas spp., Clostridiaceae, Corynebacterium renale, Flavobacteriaceae, Kytococcus sedentarius, Leuconostoc lactic, Lysinibacillus sphaericus, Pseudomonas spp., Staphylococcus aureus and Staphylococcus capitis. The greatest diversity of bacteria was detected early autumn 2008, while the lowest diversity occurred during mid-winter 2007. Bacillus cereus, Kytococcus sedentarius and Staphylococcus capitis displayed potential pathogenic properties on blood agar. Kytococcus sedentarius could be classified as potentially the most pathogenic among the isolates. All isolates displayed multiple-resistant patterns towards tested antibiotics. Corynebacterium renale and Staphylococcus aureus were least resistant bacterial species and Lysinibacillus sphaericus the most resistant. All isolates were susceptible to ciprofloxacin (CIP) and streptomycin (S), but most were resistant to erythromycin (E). Transmission electron microscopy (TEM) allowed for detailed examination of Brevundimonas spp., Pseudomonas spp. and Staphylococcus spp. The capability of Brevundimonas spp. to produce slime and store nutrients within inclusion bodies, suggests the ability of this bacterium to form biofilm and persist in the drinking water for prolonged periods. Despite the inhibitory or toxic effect of copper against bacterial growth, scanning electron microscopy (SEM) revealed the presence of biofilms as well as diatoms on red-copper coupons. Biofilm activity was also observed on reverse-osmosis (RO) filters. Since corrosion was evident on red-copper coupons, it is recommended that prospective studies also look into the significance of microbial induced corrosion (MIC) within the Potchefstroom drinking water distribution system. Other prospects include determining minimum inhibitory concentrations of isolates against antibiotics and the application of culture independent methods such as SSCP and DGGE to investigate biofilm development. The use of diatoms as an index of the drinking water quality is also suggested. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2010.
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Characterization of heterotrophic plate count (HPC) bacteria from biofilm and bulk water samples from the Potchefstroom drinking water distribution system / by S. WalterWalter, Sunette January 2009 (has links)
The presence of heterotrophic plate count (HPC) bacteria in drinking water distribution systems is usually not considered harmful to the general consumer. However, precautions must be taken regarding the immunocompromised. All water supply authorities in South Africa are lawfully required to provide consumers with high-quality drinking water that complies with South African-and international standards. This study mainly focused on the isolation, identification and characterization of HPC and other bacteria from biofilm-and bulk water samples from two sampling points located within the Potchefstroom drinking water distribution system. Based on five main objectives set out in this study, results indicated that the bulk water at the J.S. van der Merwe building was of ideal quality fit for lifetime consumption. Application of enrichment-and selective media allowed for the isolation of 12 different bacterial morphotypes. These were identified by way of biochemical-and molecular methods as Bacillus cereus, Bacillus subtilis, Brevundimonas spp., Clostridiaceae, Corynebacterium renale, Flavobacteriaceae, Kytococcus sedentarius, Leuconostoc lactic, Lysinibacillus sphaericus, Pseudomonas spp., Staphylococcus aureus and Staphylococcus capitis. The greatest diversity of bacteria was detected early autumn 2008, while the lowest diversity occurred during mid-winter 2007. Bacillus cereus, Kytococcus sedentarius and Staphylococcus capitis displayed potential pathogenic properties on blood agar. Kytococcus sedentarius could be classified as potentially the most pathogenic among the isolates. All isolates displayed multiple-resistant patterns towards tested antibiotics. Corynebacterium renale and Staphylococcus aureus were least resistant bacterial species and Lysinibacillus sphaericus the most resistant. All isolates were susceptible to ciprofloxacin (CIP) and streptomycin (S), but most were resistant to erythromycin (E). Transmission electron microscopy (TEM) allowed for detailed examination of Brevundimonas spp., Pseudomonas spp. and Staphylococcus spp. The capability of Brevundimonas spp. to produce slime and store nutrients within inclusion bodies, suggests the ability of this bacterium to form biofilm and persist in the drinking water for prolonged periods. Despite the inhibitory or toxic effect of copper against bacterial growth, scanning electron microscopy (SEM) revealed the presence of biofilms as well as diatoms on red-copper coupons. Biofilm activity was also observed on reverse-osmosis (RO) filters. Since corrosion was evident on red-copper coupons, it is recommended that prospective studies also look into the significance of microbial induced corrosion (MIC) within the Potchefstroom drinking water distribution system. Other prospects include determining minimum inhibitory concentrations of isolates against antibiotics and the application of culture independent methods such as SSCP and DGGE to investigate biofilm development. The use of diatoms as an index of the drinking water quality is also suggested. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2010.
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Mikrobiologinių rodiklių kitimas smulkintoje mėsoje laikymo metu / Changes of microbiological parameters of minced meat during storageJagminaitė, Živilė 18 June 2014 (has links)
Darbo pavadinimas: Mikrobiologinių rodiklių kitimas smulkintoje mėsoje laikymo metu.
Magistro baigiamojo darbo autorė Živilė Jagminaitė. Darbo vadovė dr. Aistė Kabašinskienė. Magistro darbas buvo atliktas Lietuvos sveikatos mokslų universitete, maisto saugos ir kokybės katedroje, per 2012-2014 laikotarpį. Darbas susideda iš: 51 puslapio, 2 lentelių, 29 paveikslų, 1 priedo.
Atitinkamas mėsos laikymas bei apdorojimas, šviežumo užtikrinimas, higieninis – sanitarinis rėžimas yra svarbūs veiksniai užtikrinant mėsos mikrobinę kokybę. Žmonės dažnai nežino kaip laikyti pusgaminius, teisingai gaminti maistą, dėl ko atsiranda pavojus susirgti infekcinėmis ligomis.
Darbo tikslas: įvertinti mikroorganizmų skaičiaus kitimą smulkintoje mėsoje, jos laikymo metu.
Rezultatai:
Aerobinių kolonijų skaičius smulkintos mėsos mėginiuose neviršijo Lietuvos Higienos normos HN 26:2006 nustatytų didžiausių leistinų ribų. Į smulkintą vištieną pridėjus prieskonių, aerobinių kolonijų sk. padidėjo 36,6 ksv/g, į smulkintą kiaulieną 1,82 ksv/g, o pridėjus kiaušinio ir džiūvėsėlių į vištieną padidėjo 8,5 ksv/g, į kiaulieną 19,09 ksv/g (p>0,05). Smulkintoje mėsoje su prieskoniais aerobinių kolonijų sk. po 3-6 val. padidėjo: vištienoje 7,4 ksv/g (p<0,05), kiaulienoje 205,32 ksv/g (p>0,05), o po 24 val.: vištienoje 169,1 ksv/g (p<0,05), kiaulienoje 466,22 ksv/g (p<0,05), o su kiaušiniu ir džiūvėsėliais aerobinių kolonijų sk. po 3-6 val. padidėjo: vištienoje 9,6 ksv/g (p>0,05), kiaulienoje 0,45 ksv/g (p<0,05)... [toliau žr. visą tekstą] / Title of the thesis: Changes of microbiological parameters of minced meat during storage.
The author of this Master work is Živilė Jagminaitė. Work advisor: dr. Aistė Kabašinskienė. The Master work was completed in Lithuanian university of health sciences, Department of food safety and quality, during 2011-2012 period. Work consists of: 51 pages, 2 tables, 29 illustrations, 1 supplement.
Appropriate storage and meat processing, freshness assurance and hygienic-sanitary regimes are important factors when ensuring meat microbial quality. In often cases people don‘t know how to hold semi-cooked food properly, how to correctly prepare food, resulting in the risk of developing infectious diseases.
Thesis aim: to evaluate the change in population of microbes in minced meat during the period of its storage.
Results:
Aerobic colony count in samples of minced meat did not exceed those of Lithuanian Hygiene Standards HN 26:2006 maximum allowed limits. When added spices to minced chicken, aerobic colony count has increased by 36,6 CFU/g, to pork by 8,49 CFU/g, and once added egg and bread crumbs to minced chicken increased by 8,5 CFU/g, to pork by 12,1 CFU/g (p>0,05). In the holding period of 3 to 6 hours, the count of aerobic colony in minced chicken with spices has increased by 7,4 CFU/g, in pork by 205,32CFU/g (p>0,05) and after 24 hours in chicken reached by 169,1 CFU/g (p<0,05), in pork by 396,06 CFU/g (p>0,05). For egg and bread crumbs 3 to 6 hours has increased by 9,6 CFU/g... [to full text]
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Skirtingų veislių karvių melžimo savybių palyginimas / Comparison of milking properties of cows of different breedsLembertas, Klaudijus 18 June 2014 (has links)
Šio darbo tikslas - palyginti skirtingų veislių karvių melžimo savybes.
Darbo uždaviniai. 1. Išanalizuoti Lietuvos juodmargių ir Lietuvos žalųjų veislių karvių melžimo savybes. 2. Nustatyti laktacijos įtaką karvių melžimo savybėms. 3. Nustatyti melžimo laiko įtaką tiriamų veislių karvių pieno kiekiui ir vidutiniam pieno atidavimo greičiui. 4. Įvertinti ūkio įtaką melžimo savybėms. 5. Atlikti somatinių ląstelių skaičiaus (SLS) ir melžimo savybių koreliacinę analizę.
Išvados: 1) Išanalizavus tirtų Lietuvos juodmargių ir Lietuvos žalųjų veislių karvių pagrindinių melžimo savybių rezultatus nustatyta, kad: 1.1. Vidutinis pieno tekėjimo greitis Lietuvos žalųjų (0,02 kg/min) buvo didesnis nei Lietuvos juodmargių veislės karvių (p<0,05). 1.2. Didžiausia pieno tekėjimo srovė buvo Lietuvos juodmargių buvo 0,05 kg/min didesnė nei Lietuvos žalųjų (p>0,05). 1.3. Melžimo laikas 0,11 min. buvo ilgesnis Lietuvos žalųjų veislės karvių. 2) Atlikus skirtingų laktacijų karvių produktyvumo ir melžimo savybių analizę, nustatyta, kad I laktacijos karvių bendras pieno kiekis (kg) ir vidutinis pieno atidavimo greitis (kg/min). buvo didžiausias Lietuvos žalųjų karvių, tačiau I laktacijos karvių melžimo trukmė buvo ilgesnė nei Lietuvos juodmargių veislės karvių. 3) Nustatyta, kad Lietuvos juodmargių, kurios melžėsi ilgiau nei 6 minutes buvo 4,73% daugiau nei Lietuvos žalųjų veislių karvių (p<0,05) Iš pateiktų duomenų matome, kad Lietuvos žalųjų buvo beveik 5% daugiau nei Lietuvos juodmargių, kurios... [toliau žr. visą tekstą] / The aim of this thesis was to assess milking properties of cows of different breeds.
Objectives of the paper: 1. Analyze the Lithuanian Black and White and Lithuanian Red cows milking qualities. 2. Determine lactation influence milking performance. 3. Determine the time of milking cows tested influence on milk yield and milk the average speed of the output. 4. To evaluate the farm impact of the milking properties. 5. Perform somatic cell count and milking performance correlation analysis.
The scientific research was carried out between 2012-2014 at the Department of Animal Breeding of the Veterinary Academy of the Lithuanian University of Health Sciences and 2 dairy farms.
Descriptive statistics: the average of investigated traits (M), standard errors were calculated using the EXEL and “R” (The R Project for Statistical Computing, 2012) statistical packages
Milking properties were analyzed with the help of the device Lactocorder. In total 81 cows of Lithuanian black and white and Lithuanian red cattle breeds from two farms were analyzed. Lithuanian black and white cows constituted 71.6 percent, while Lithuanian red cows constituted 28.4 percent. According to lactation all analyzed cows were divided into the following three groups: lactation I, lactation II, lactation III and later. The first lactation cows constituted 6.1 % , the second lactation cows constituted 19.75 % and the group of cows of the third and later lactation was the largest and constituted 74.07 % .
The... [to full text]
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